Severity Medium
U0307

PCM-GPCM Software Mismatch Code U0307

📅 Last reviewed: July 2026
What does the U0307 code mean?

The Powertrain Control Module (PCM) has detected a software or calibration ID incompatibility with the Glow Plug Control Module (GPCM). This occurs when the software version or calibration ID transmitted by the GPCM over the CAN bus does not match the expected values programmed in the PCM for the specific vehicle configuration, preventing proper glow plug system management.

Medium
Severity
Variable
Typical Cost
Medium
Frequency

1. Commonly Affected Makes

This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.

2. Most Common Causes

3. Symptoms You Will Notice

4. Step-by-Step Diagnosis

1

Verify that the GPCM part number and software version match the vehicle specifications

2

Check for any related CAN bus communication codes

3

Attempt to reprogram the GPCM with the correct calibration using factory scan tool

4

If reprogramming fails, replace the GPCM and perform proper programming

5. Frequently Asked Questions

Is it safe to drive?

You can drive short distances, but cold starting may be difficult and the glow plug system may not function correctly. It is recommended to address the issue promptly.

How much does it cost to fix?

Reprogramming typically costs $100-$200. If GPCM replacement is needed, total cost including parts and labor ranges from $300 to $600.

6. Related Codes

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